1. Field of the Invention
The present invention relates to a process for preparing a mixture of fatty acids containing eicosapentaenoic acid and, more particularly, to a process for preparing a fatty acid mixture containing a high concentration of eicosapentaenoic acid from a lipid component extracted from marine chlorella.
2. Description of the Prior Art
5,8,11,14,17-Eicosapentaenoic acid (hereafter referred to as EPA) is a substance that has recently been recognized as an agent for preventing and curing cerebral thrombosis and arteriosclerosis. It is known that EPA is contained in fish oils and oils and fats of marine plants (algae). Nowadays, it is extracted and purified wholly from oils of fish such as sardines or the like. Among fish oils, the ones containing a high concentration of EPA contain EPA in an amount of approximately 20% by weight of the total fatty acids. For use as health food, a composition of fatty acids is used in which the concentration of EPA is increased to approximately 25 to 30%. For use as pharmaceuticals, a fatty acid composition containing higher than 90% of EPA has been prepared experimentally.
Since, however, fish oils contain a high concentration of highly unsaturated fatty acids (containing a number of carbon-carbon double bonds) such as docosahexaenoic acid and the like similar in nature and structure to EPA, it is not easy to increase the concentration of EPA in the fatty acid composition obtained from fish oils. Particularly, pharmaceuticals require a fatty acid mixture containing EPA in a concentration of 90% or more. In order to attain such a high EPA concentration, a complex combination of treatment procedures such as urea adduct process, solvent extraction, fractional distillation and column chromatography is required.